Maternal depression and a common class of antidepressants can alter a crucial period of language development in babies, according to a new study by researchers at the University of British Columbia, Harvard University and the Child & Family Research Institute (CFRI) at BC Children's Hospital. Published today in the Proceedings of the National Academy of Sciences, the study finds that treatment of maternal depression with serotonin reuptake inhibitors (SRIs) can accelerate babies' ability to attune to the sounds and sights of their native language, while maternal depression untreated by SRIs may prolong the period of tuning. "This study is among the first to show how maternal depression and its treatment can change the timing of language development in babies," says Prof. Janet Werker of UBC's Dept. of Psychology, the study's senior author. "At this point, we do not know if accelerating or delaying these milestones in development has lasting consequences on later language acquisition, or if alternate developmental pathways exist. We aim to explore these and other important questions in future studies."